Gordon's Gin are introducing a service that can reward delayed rail passengers with either a half price or a free gin and tonic, and apparently uses an intelligent algorithm to monitor real-time train delays.

The service, called #YayDelay, is currently only available at Waterloo Station in London, but Gordon's say they plan to go live in other stations across the country throughout the year.

The service works by allowing customers to unlock a discounted drink code by tweeting their frustrations about the delay, which can be redeemed at the Slug and Lettuce within the station.

There's a catch though: it's only available between 5-6pm on Fridays, and customers will need to keep their eyes peeled on yaydelay.com website to see if the volume of train delays and tweets triggers a free G&T.